From 7e9081c5aac73b8a0bc22e0b3e7a12c3e9cf5256 Mon Sep 17 00:00:00 2001 From: Gustavo Padovan Date: Fri, 13 Jan 2017 12:22:09 -0200 Subject: drm/fence: fix memory overwrite when setting out_fence fd Currently if the userspace declares a int variable to store the out_fence fd and pass it to OUT_FENCE_PTR the kernel will overwrite the 32 bits above the int variable on 64 bits systems. Fix this by making the internal storage of out_fence in the kernel a s32 pointer. Reported-by: Chad Versace Signed-off-by: Gustavo Padovan Fixes: beaf5af48034 ("drm/fence: add out-fences support") Cc: Daniel Vetter Cc: Rafael Antognolli Cc: Laurent Pinchart Acked-by: Laurent Pinchart Reviewed-and-Tested-by: Chad Versace Link: http://patchwork.freedesktop.org/patch/msgid/1484317329-9293-1-git-send-email-gustavo@padovan.org --- drivers/gpu/drm/drm_atomic.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) (limited to 'drivers/gpu/drm/drm_atomic.c') diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c index 60697482b94c..50f5cf7b69d1 100644 --- a/drivers/gpu/drm/drm_atomic.c +++ b/drivers/gpu/drm/drm_atomic.c @@ -291,15 +291,15 @@ drm_atomic_get_crtc_state(struct drm_atomic_state *state, EXPORT_SYMBOL(drm_atomic_get_crtc_state); static void set_out_fence_for_crtc(struct drm_atomic_state *state, - struct drm_crtc *crtc, s64 __user *fence_ptr) + struct drm_crtc *crtc, s32 __user *fence_ptr) { state->crtcs[drm_crtc_index(crtc)].out_fence_ptr = fence_ptr; } -static s64 __user *get_out_fence_for_crtc(struct drm_atomic_state *state, +static s32 __user *get_out_fence_for_crtc(struct drm_atomic_state *state, struct drm_crtc *crtc) { - s64 __user *fence_ptr; + s32 __user *fence_ptr; fence_ptr = state->crtcs[drm_crtc_index(crtc)].out_fence_ptr; state->crtcs[drm_crtc_index(crtc)].out_fence_ptr = NULL; @@ -512,7 +512,7 @@ int drm_atomic_crtc_set_property(struct drm_crtc *crtc, state->color_mgmt_changed |= replaced; return ret; } else if (property == config->prop_out_fence_ptr) { - s64 __user *fence_ptr = u64_to_user_ptr(val); + s32 __user *fence_ptr = u64_to_user_ptr(val); if (!fence_ptr) return 0; @@ -1915,7 +1915,7 @@ EXPORT_SYMBOL(drm_atomic_clean_old_fb); */ struct drm_out_fence_state { - s64 __user *out_fence_ptr; + s32 __user *out_fence_ptr; struct sync_file *sync_file; int fd; }; @@ -1952,7 +1952,7 @@ static int prepare_crtc_signaling(struct drm_device *dev, return 0; for_each_crtc_in_state(state, crtc, crtc_state, i) { - u64 __user *fence_ptr; + s32 __user *fence_ptr; fence_ptr = get_out_fence_for_crtc(crtc_state->state, crtc); -- cgit v1.2.3 From 92c715fca907686f5298220ece53423e38ba3aed Mon Sep 17 00:00:00 2001 From: Maarten Lankhorst Date: Tue, 31 Jan 2017 10:25:25 +0100 Subject: drm/atomic: Fix double free in drm_atomic_state_default_clear drm_atomic_helper_page_flip and drm_atomic_ioctl set their own events in crtc_state->event. But when it's set the event is freed in 2 places. Solve this by only freeing the event in the atomic ioctl when it allocated its own event. This has been broken twice. The first time when the code was introduced, but only in the corner case when an event is allocated, but more crtc's were included by atomic check and then failing. This can mostly happen when you do an atomic modeset in i915 and the display clock is changed, which forces all crtc's to be included to the state. This has been broken worse by adding in-fences support, which caused the double free to be done unconditionally. [IGT] kms_rotation_crc: starting subtest primary-rotation-180 ============================================================================= BUG kmalloc-128 (Tainted: G U ): Object already free ----------------------------------------------------------------------------- Disabling lock debugging due to kernel taint INFO: Allocated in drm_atomic_helper_setup_commit+0x285/0x2f0 [drm_kms_helper] age=0 cpu=3 pid=1529 ___slab_alloc+0x308/0x3b0 __slab_alloc+0xd/0x20 kmem_cache_alloc_trace+0x92/0x1c0 drm_atomic_helper_setup_commit+0x285/0x2f0 [drm_kms_helper] intel_atomic_commit+0x35/0x4f0 [i915] drm_atomic_commit+0x46/0x50 [drm] drm_mode_atomic_ioctl+0x7d4/0xab0 [drm] drm_ioctl+0x2b3/0x490 [drm] do_vfs_ioctl+0x69c/0x700 SyS_ioctl+0x4e/0x80 entry_SYSCALL_64_fastpath+0x13/0x94 INFO: Freed in drm_event_cancel_free+0xa3/0xb0 [drm] age=0 cpu=3 pid=1529 __slab_free+0x48/0x2e0 kfree+0x159/0x1a0 drm_event_cancel_free+0xa3/0xb0 [drm] drm_mode_atomic_ioctl+0x86d/0xab0 [drm] drm_ioctl+0x2b3/0x490 [drm] do_vfs_ioctl+0x69c/0x700 SyS_ioctl+0x4e/0x80 entry_SYSCALL_64_fastpath+0x13/0x94 INFO: Slab 0xffffde1f0997b080 objects=17 used=2 fp=0xffff92fb65ec2578 flags=0x200000000008101 INFO: Object 0xffff92fb65ec2578 @offset=1400 fp=0xffff92fb65ec2ae8 Redzone ffff92fb65ec2570: bb bb bb bb bb bb bb bb ........ Object ffff92fb65ec2578: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ffff92fb65ec2588: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ffff92fb65ec2598: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ffff92fb65ec25a8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ffff92fb65ec25b8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ffff92fb65ec25c8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ffff92fb65ec25d8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b kkkkkkkkkkkkkkkk Object ffff92fb65ec25e8: 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b 6b a5 kkkkkkkkkkkkkkk. Redzone ffff92fb65ec25f8: bb bb bb bb bb bb bb bb ........ Padding ffff92fb65ec2738: 5a 5a 5a 5a 5a 5a 5a 5a ZZZZZZZZ CPU: 3 PID: 180 Comm: kworker/3:2 Tainted: G BU 4.10.0-rc6-patser+ #5039 Hardware name: /NUC5PPYB, BIOS PYBSWCEL.86A.0031.2015.0601.1712 06/01/2015 Workqueue: events intel_atomic_helper_free_state [i915] Call Trace: dump_stack+0x4d/0x6d print_trailer+0x20c/0x220 free_debug_processing+0x1c6/0x330 ? drm_atomic_state_default_clear+0xf7/0x1c0 [drm] __slab_free+0x48/0x2e0 ? drm_atomic_state_default_clear+0xf7/0x1c0 [drm] kfree+0x159/0x1a0 drm_atomic_state_default_clear+0xf7/0x1c0 [drm] ? drm_atomic_state_clear+0x30/0x30 [drm] intel_atomic_state_clear+0xd/0x20 [i915] drm_atomic_state_clear+0x1a/0x30 [drm] __drm_atomic_state_free+0x13/0x60 [drm] intel_atomic_helper_free_state+0x5d/0x70 [i915] process_one_work+0x260/0x4a0 worker_thread+0x2d1/0x4f0 kthread+0x127/0x130 ? process_one_work+0x4a0/0x4a0 ? kthread_stop+0x120/0x120 ret_from_fork+0x29/0x40 FIX kmalloc-128: Object at 0xffff92fb65ec2578 not freed Fixes: 3b24f7d67581 ("drm/atomic: Add struct drm_crtc_commit to track async updates") Fixes: 9626014258a5 ("drm/fence: add in-fences support") Cc: # v4.8+ Cc: Daniel Vetter Signed-off-by: Maarten Lankhorst Reviewed-by: Daniel Vetter Reviewed-by: Gustavo Padovan Signed-off-by: Daniel Vetter Link: http://patchwork.freedesktop.org/patch/msgid/1485854725-27640-1-git-send-email-maarten.lankhorst@linux.intel.com --- drivers/gpu/drm/drm_atomic.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) (limited to 'drivers/gpu/drm/drm_atomic.c') diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c index 50f5cf7b69d1..fdfb1ec17e66 100644 --- a/drivers/gpu/drm/drm_atomic.c +++ b/drivers/gpu/drm/drm_atomic.c @@ -2032,13 +2032,16 @@ static void complete_crtc_signaling(struct drm_device *dev, } for_each_crtc_in_state(state, crtc, crtc_state, i) { + struct drm_pending_vblank_event *event = crtc_state->event; /* - * TEST_ONLY and PAGE_FLIP_EVENT are mutually - * exclusive, if they weren't, this code should be - * called on success for TEST_ONLY too. + * Free the allocated event. drm_atomic_helper_setup_commit + * can allocate an event too, so only free it if it's ours + * to prevent a double free in drm_atomic_state_clear. */ - if (crtc_state->event) - drm_event_cancel_free(dev, &crtc_state->event->base); + if (event && (event->base.fence || event->base.file_priv)) { + drm_event_cancel_free(dev, &event->base); + crtc_state->event = NULL; + } } if (!fence_state) -- cgit v1.2.3